avcodec/apedec: simplify sign conversion

Signed-off-by: Zeng Zhaoxiu <zhaoxiu.zeng@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
zhaoxiu.zeng 2015-02-14 00:56:28 +08:00 committed by Michael Niedermayer
parent b11a187575
commit ac7fc444ee

View File

@ -505,10 +505,7 @@ static inline int ape_decode_value_3860(APEContext *ctx, GetBitContext *gb,
rice->k++;
/* Convert to signed */
if (x & 1)
return (x >> 1) + 1;
else
return -(x >> 1);
return ((x >> 1) ^ ((x & 1) - 1)) + 1;
}
static inline int ape_decode_value_3900(APEContext *ctx, APERice *rice)
@ -542,10 +539,7 @@ static inline int ape_decode_value_3900(APEContext *ctx, APERice *rice)
update_rice(rice, x);
/* Convert to signed */
if (x & 1)
return (x >> 1) + 1;
else
return -(x >> 1);
return ((x >> 1) ^ ((x & 1) - 1)) + 1;
}
static inline int ape_decode_value_3990(APEContext *ctx, APERice *rice)
@ -588,10 +582,7 @@ static inline int ape_decode_value_3990(APEContext *ctx, APERice *rice)
update_rice(rice, x);
/* Convert to signed */
if (x & 1)
return (x >> 1) + 1;
else
return -(x >> 1);
return ((x >> 1) ^ ((x & 1) - 1)) + 1;
}
static void decode_array_0000(APEContext *ctx, GetBitContext *gb,
@ -634,12 +625,8 @@ static void decode_array_0000(APEContext *ctx, GetBitContext *gb,
}
}
for (i = 0; i < blockstodecode; i++) {
if (out[i] & 1)
out[i] = (out[i] >> 1) + 1;
else
out[i] = -(out[i] >> 1);
}
for (i = 0; i < blockstodecode; i++)
out[i] = ((out[i] >> 1) ^ ((out[i] & 1) - 1)) + 1;
}
static void entropy_decode_mono_0000(APEContext *ctx, int blockstodecode)